Hi, On Tue, 06 Jul 2010 11:02:41 +0200, Łukasz_Wójcicki wrote: > I'am using kernel 2.6.20 with nilf_utils-2-0-18 and nilfs kernel module > 2-0-20 . > > <1>Unable to handle kernel NULL pointer dereference at virtual address > 00000000 > <1>pgd = c4eb0000 > <1>[00000000] *pgd=c4e2d031, *pte=00000000, *ppte=00000000 > <4>Internal error: Oops: 17 [#1] > <4>Modules linked in: > <4>CPU: 0 > <4>PC is at nilfs_btree_lookup_dirty_buffers+0x10c/0x1ec > <4>LR is at 0xc4c99b24 <snip> Could you try the following patch to narrow down the cause? There is a function lacking range check in the btree code. This patch will catch the defect if the oops comes from a range error. I'm now reviewing the btree code to find out root cause of the range error. Thanks, Ryusuke Konishi --- diff --git a/fs/btree.c b/fs/btree.c index beb11fe..9622ff4 100644 --- a/fs/btree.c +++ b/fs/btree.c @@ -2007,6 +2007,15 @@ static void nilfs_btree_add_dirty_buffer(struct nilfs_btree *btree, node = (struct nilfs_btree_node *)bh->b_data; key = nilfs_btree_node_get_key(node, 0); level = nilfs_btree_node_get_level(node); + if (level < NILFS_BTREE_LEVEL_NODE_MIN || + level >= NILFS_BTREE_LEVEL_MAX) { + dump_stack(); + printk(KERN_CRIT + "%s: invalid btree level: %d (ino=%lu)\n", __func__, + level, NILFS_BMAP_I(&btree->bt_bmap)->vfs_inode.i_ino); + return; + } + list_for_each(head, &lists[level]) { cbh = list_entry(head, struct buffer_head, b_assoc_buffers); cnode = (struct nilfs_btree_node *)cbh->b_data; -- 1.6.6.2 ��.n��������+%������w��{.n�����{��x�~���n�r������&��z�ޗ�zf���h���~����������_��+v���)ߣ�